Queen's Gambit Declined Slav - Schlechter variation
1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 g6
White advances the queen's pawn to d4. Black moves the queen's pawn to d5. White pushes the c-pawn to c4.
Black moves the c-pawn to c6. White develops the knight to f3. Black develops the knight to f6.
White jumps the knight to c3. Black pushes the g-pawn to g6.